In algebra, given a ring R, the category of left modules over R is the category whose objects are all left modules over R and whose morphisms are all module homomorphisms between left R-modules. For example, when R is the ring of integers Z, it is the same thing as the category of abelian groups. The category of right modules is defined in a similar way.
One can also define the category of bimodules over a ring R but that category is equivalent to the category of left (or right) modules over the enveloping algebra of R (or over the opposite of that).
Note: Some authors use the term module category for the category of modules. This term can be ambiguous since it could also refer to a category with a monoidal-category action.[1]
^"module category in nLab". ncatlab.org.
and 25 Related for: Category of modules information
ring R, the categoryof left modules over R is the category whose objects are all left modules over R and whose morphisms are all module homomorphisms...
entire categoryofmodules. Injective resolutions measure how far from injective a module is in terms of the injective dimension and represent modules in...
ring, then the categoryof finitely generated left modules over R is abelian. In particular, the categoryof finitely generated modules over a noetherian...
class of projective modules enlarges the class of free modules (that is, modules with basis vectors) over a ring, keeping some of the main properties of free...
sheaf of O-modules or simply an O-module over a ringed space (X, O) is a sheaf F such that, for any open subset U of X, F(U) is an O(U)-module and the...
one can consider a category C enriched over the monoidal categoryofmodules over a commutative ring R, called an R-linear category. In other words, each...
{\mathcal {A}}} be an abelian category. (Examples include the categoryofmodules over a ring and the categoryof sheaves of abelian groups on a topological...
combines several modules into a new module. The most familiar examples of this construction occur when considering vector spaces, which are modules over a field...
spaces, abelian groups, R-modules, or R-algebras into monoidal categories. Monoidal categories can be seen as a generalization of these and other examples...
particular, any non-trivial category with a zero object, such as an abelian category, is not Cartesian closed. So the categoryofmodules over a ring is not Cartesian...
let R-Mod be the categoryofmodules over R. (One can take this to mean either left R-modules or right R-modules.) For a fixed R-module A, let T(B) = HomR(A...
algebra, a module homomorphism is a function between modules that preserves the module structures. Explicitly, if M and N are left modules over a ring...
representation theory, the stable modulecategory is a category in which projectives are "factored out." Let R be a ring. For two modules M and N over R, define...
compact modules, also called pure-injective modules, are modules that have a certain "nice" property which allows the solution of infinite systems of equations...
A} , there is an equivalence ofcategories from A {\displaystyle A} -modules to quasi-coherent sheaves, taking a module M {\displaystyle M} to the associated...
category C {\displaystyle {\mathcal {C}}} , and the categoryofmodules over the ring is a categoryof functors defined on C {\displaystyle {\mathcal {C}}}...
over R, or a moduleof finite type. Related concepts include finitely cogenerated modules, finitely presented modules, finitely related modules and coherent...
regarded as Z-modules, so the categoryof abelian groups is also a symmetric, closed monoidal category. A symmetric compact closed category is a symmetric...
related to R-modules, but where this map is an isomorphism turns out to be the categoryof R [ S − 1 ] {\displaystyle R[S^{-1}]} -modules. Here R [ S −...
of the ∞-category of perfect modules over R (a perfect module being defined as a compact object in the ∞-categoryofmodule spectra.) G-spectrum J. Lurie...
combines several modules into a new, larger module. The direct sum ofmodules is the smallest module which contains the given modules as submodules with...
similar notion of duality in 1958. Rings are commonly studied in terms of their modules, as modules can be viewed as representations of rings. Every ring...
R-Mod the categoryof left R-modules and by Mod-R the categoryof right R-modules (if R is commutative, the two categories coincide). Fix a module B in R-Mod...